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  <title>Document</title>
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<body>
  <script>
    var findTheDifference = function (s, t) {
      s = s.split('').sort().join('');
      t = t.split('').sort().join('');

      for (let i = 0; i < t.length; i++) {
        if (s[i] != t[i]) {
          return t[i];
        }
      }
    };
    console.log(findTheDifference("abcd", "abcde"));
  </script>
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